Development of modified integrated water quality index to assess the surface water quality: a case study of Tuo River, China.

Water quality evaluation is an important step in water environment control and management. The water quality index (WQI) is considered to be an effective method for water quality evaluation. However, when constructing the WQI, the contribution of the lower threshold limits of water quality parameters to water quality has received little attention.

Spatial variation and source apportionment of surface water pollution in the Tuo River, China, using multivariate statistical techniques.

The increasingly serious water pollution of rivers has attracted wide attention from all countries in the world. Investigating spatial variations of water pollution and source apportionment is particularly important for the effective management of river quality. The water samples collected every two months at 31 sampling sites containing 12 water quality parameters during 2018 and 2019 were analyzed to investigate the spatial patterns and the apportionment of the pollutants in the Tuo River.